Encode a 32 bit FLAC?

[Undead Sega]

Hi once again guys, it has ben awhile for me here, however I've been having a problem my Bluray's TrueHD stream, as my media player does not support it (I have muxed my bluray into an mkv so I can take it round with me on my MP for those who doesnt have an actual standalone player).

The solution to this I believe is to convert it to a Flac to retain all of its glorious qualiy, however everytime I do so with eac3to it keeps downsampling it to 16bit and this is not what I want. playing the actual stream in VLC informs me that it is 32bit and this is what I want to keep. After some research I might be willing to take it down 24bit.

I've looked everywhere and I cannot find a way on how to encode a 32bit FLAC file, and I was hoping someone here with more knowlege of the audio codecs and software can help me on this :)

[Gser]

Dolby TrueHD bitstream can carry sample depths up to 24 bits/sample and audio sample rates up to 192 kHz are supported. It is 24bit not 32bit. Most likely whatever is decoding it is upsampling it to 32bit.

[tebasuna51]

..., however everytime I do so with eac3to it keeps downsampling it to 16bit and this is not what I want...

When eac3to downsample to 16 bits is beacause eac3to check the 8 less significant bits of 24 bits samples, and found than its are always 0. Then the real bitdepth is 16 bits.

[Undead Sega]

Well, i was playing it through VLC player and looking at the Codec details, it clearly states to me that the Bit per sample is 32, I'm pretty sure that no upsampling is been done. However either way, I was still wondering if it is possible to encode either a 24bit or 32bit FLAC? Still cant seem to find a way.

[pandy]

IMHO only INTEGER formats are used to store audio in loss-less way (ie on CD/DVD/BD) so FLOAT appears only on decoder output.

http://lists.xiph.org/pipermail/flac-dev/2009-August/002673.html
http://en.wikipedia.org/wiki/FLAC#Technical_details

[Undead Sega]

I see, that's quite interesting and informative. In that case (for now), how would I encode for 24bit FLAC from my TrueHD stream? application keep reducing it to 16bit as if it doesnt support any higher when it technically does.

[tebasuna51]

In that case (for now), how would I encode for 24bit FLAC from my TrueHD stream?.
Using a 24 bit source.

application keep reducing it to 16bit as if it doesnt support any higher when it technically does.
If eac3to output 16 bits only means the source is only 16 bits.
You can't gain quality upsamplig a 16 bits to 24 bit.

Look how work eac3to:
TrueHD, 5.1 channels, 48kHz, dialnorm: -27dB
Removing TrueHD dialog normalization...
Decoding with libav/ffmpeg...
Encoding FLAC with libFlac...
Creating file "D:\Test\AudioN\TrueHD\001_6_24_48.thd_.flac"...
Original audio track, L+R+C+LFE: constant bit depth of 16 bits.
Original audio track, SL+SR: constant bit depth of 24 bits.
eac3to processing took 3 seconds.
Done.

------------------------------------------------------------------------------
FLAC, 5.1 channels, 0:00:17, 24 bits, 2183kbps, 48kHz
eac3to analyze all channels to know bitdepth.
Like at least the channels SL+SR are 24 bits the flac output is 24 bits.